hard one to say, been so many talented players over the years in different styles
jimmy page has got to be up there with the best, gary moore, steve vai, joe satriani, robert Fripp the list goes on
wind the clock back a few decades and the likes of Django Rheinhardt was way ahead of his time and robert johnson pretty much invented the modern syle way back in the 1920's
currently top of my ipod playlist is Rodrigo Y Gabriela - flamenco guitarists that must have bionic fingers fusing flamenco with zeppelin, metallica and the like!